Hi, response to your questions on the selling section about VM30's
Those particular carbs are designed for piston ported two stroke motors.
With reed valve motor it would be better to use the emulsion tunes you have in the 26mm carbs. (they do fit and work properly)
You can also modify the primary choke 'hoods' to change fueling characteristics
Only problem I found with RD400, expansion chamers and 32~34mm carbs, steering is way too light, it's real difficult to steer with front wheel 18"in the air (18" is about 450mm, just in case you don't do 'Imperial measurements'
)
30mm should be slightly tamer, that size carb will support around 40+bhp per cylinder, with the 'right' exhaust and some porting, 75~80bhp is pretty easy to get
Motor doesn't last as long though, needs frequent piston ring and piston changing, pistons every second set of rings (about 350~500km)
Modified stock reed blocks work better than just about any aftermarket set, it just takes a bunch of time to get everything flowing properly and can only be done by hand with files and emery paper 8) (I've tried die grinders, carbide burrs, etc, not much use)
I'm not sure just how much you can do, I've heard the TUV inspection is really strict on non standard parts?